Phosphoglucomutase reaction with nucleophilic reagents have been studied extensively. In addition to the thiol compounds we included hydroxylamine and its derivatives. Regarding the phagocytosis stimulating tetrapeptide tuftsin (Thr-Lys-Pro-Arg) we have located it in the Fc section of the heavy chain cleaved at the argenine end. It is present only in the leucophilic fractions of gamma-globin. For its activity, the presence of sialic acid on the membrane is necessary. We have reported in detail its absence in splenectomized humans and reported two more families with tuftsin deficiency. We have reported extensively and in detail its isolation structure and chemical synthesis. We found that it stimulates not only phagocytosis but the motility of the PMN leucocytes as well as its longevity. It also stimulates phagocytosis of macrophages. We have reported its deficiency in acute myelogenous leukemias and myelofibrosis. We have indicated above what we have done in those two areas and we propose to continue with the same type of work.